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11.
In this study, we describe what we term a Blue Transition, defined as the passage from fish biomass reduction to recovery in exploited aquatic resources, enabled by aquaculture. A Blue Transition is a key component of emergent “blue” discourses which support that the expansion of aquaculture would relieve pressure on declining capture fisheries, thus contributing to global food security, particularly of the poorest populations. Based on global secondary data and the case of Chile, we explore the evidence of such claim and the implications of a Blue Transition for fisheries and aquaculture development. In 2012, worldwide aquaculture production surpassed wild captures; nevertheless, such turnaround would have not taken place without China's contribution. In Chile, this turnaround occurred in 2014, concurrently with the lowest industrial landings registered since the 1960s (1,227,359 tons). Chile's aquaculture is not relieving wild fisheries or satisfying food demands of the lower income population, in the country or elsewhere. Salmon, the main aquaculture product, is destined mainly to Japan, Russia and United States where, due to its high prices, it is consumed mostly by wealthy consumers. For the case at hand, evidence suggests that a blue transition may be underway but is going in the wrong direction: from what may have been sustainable fisheries management before the 1970s to the overexploited wild fisheries of today.  相似文献   
12.
Wicked problems are typically social justice and social change problems, complex and messy. They mobilize opposed views about the essential nature of the issues, their relative importance and adequate responses. We assert that illegal fishing in small-scale fisheries (SSF) can be considered a wicked problem and our aim is to test this assertion. We relied on a conceptual framework that defines wicked problems as (1) indefinable and non-generalizable, (2) ambiguously bounded, (3) temporally exacting, (4) repercussive, (5) doubly hermeneutic and (6) morally consequential. We applied a qualitative research approach based on field data comprising three illustrative Chilean SSF, whereas secondary data complemented the analysis. The results demonstrate that illegal fishing fits most of the requirements of a wicked policy problem. It is indefinable and non-generalizable, with different representations and uncertainty about its nature, magnitude and effects. Depictions of the nature of the problem varied from a lack of regulations' legitimacy, to a ‘combat’ to be won. It is ambiguously bounded, caused by interrelated sub-problems (e.g. poverty, access), involving multiple policy sectors, administrative scales and actors. It is also temporally exacting and repercussive as it lacks criteria to prove that a solution has been reached and the implications of alternative solutions (e.g. self-regulation) are unknown. As long as illegal fishing is reframed as a wicked problem, the stakeholders involved can also recognize that there are no perfect solutions and therefore promote a mix of substandard governance approaches.  相似文献   
13.
Spodoptera frugiperda is a polyphagous pest of several crops of economic importance. Nowadays, the insect is broadly distributed in America and, recently, in Africa, Asia, and Australia. The species has diverged into corn and rice strains. The role of the gut microbiota in insect physiology is relevant due to its participation in crucial functions. However, knowledge of seasonal variations that alter the gut microbiome in pests is limited. Gut microbiome composition between the dry and rainy seasons was analyzed with cultured and uncultured approaches in S. frugiperda corn strain larvae collected at Northwest Colombia, as seasonal microbiome changes might fluctuate due to environmental changes. On the basis of culture-dependent methods, results show well-defined microbiota with bacterial isolates belonging to Enterococcus, Klebsiella (Enterobacteriales: Enterobacteriaceae), Enterobacter (Enterobacterales: Enterobacteriaceae), and Bacillus (Bacillales: Bacillaceae) genera. The community composition displayed a low bacterial diversity across all samples. The core community detected with uncultured methods was composed of Enterococcus, Erysipelatoclostridium (Erysipelotrichales: Erysipelotrichaceae), Rasltonia (Burkholderiales: Burkholderiaceae), and Rhizobium (Hyphomicrobiales: Rhizobiaceae) genera, and Enterobacteriaceae family members. Significant differences in microbiome diversity were observed between the two seasons. The relative abundance of Erysipelatoclostridium was high in the dry season, while in the phylotype ZOR0006 (Erysipelotrichales: Erysipelotrichaceae) and Tyzzerella (Lachnospirales: Lachnospiraceae) genus, the relative abundance was high in the rainy season. The overall low gut bacterial diversity observed in the S. frugiperda corn strain suggests a strong presence of antagonist activity as a selection factor possibly arising from the host, the dominant bacterial types, or the material ingested. Targeting the stability and predominance of this core microbiome could be an additional alternative to pest control strategies, particularly in this moth.  相似文献   
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15.
ABSTRACT: The Extradomain A from fibronectin (EDA) has an immunomodulatory role as fusion protein with viral and tumor antigens, but its effect when administered with bacteria has not been assessed. Here, we investigated the adjuvant effect of EDA in mice immunizations against Salmonella enterica subspecies enterica serovar Enteritidis (Salmonella Enteritidis). Since lipopolysaccharide (LPS) is a major virulence factor and the LPS O-polysaccharide (O-PS) is the immunodominant antigen in serological diagnostic tests, Salmonella mutants lacking O-PS (rough mutants) represent an interesting approach for developing new vaccines and diagnostic tests to differentiate infected and vaccinated animals (DIVA tests). Here, antigenic preparations (hot-saline extracts and formalin-inactivated bacterins) from two Salmonella Enteritidis rough mutants, carrying either intact (SEΔwaaL) or deep-defective (SEΔgal) LPS-Core, were used in combination with EDA. Biotinylated bacterins, in particular SEΔwaaL bacterin, decorated with EDAvidin (EDA and streptavidin fusion protein) improved the protection conferred by hot-saline or bacterins alone and prevented significantly the virulent infection at least to the levels of live attenuated rough mutants. These findings demonstrate the adjuvant effect of EDAvidin when administered with biotinylated bacterins from Salmonella Enteritidis lacking O-PS and the usefulness of BEDA-SEΔwaaL as non-live vaccine in the mouse model.  相似文献   
16.
This study was designed to optimize calcium-45 (45Ca) sample preparation method in a Liquid Scintillation Counter (LSC) for use with vegetables and soil samples. Different tests were conducted on fruit and soil samples to determine the best conditions related to drying, time and centrifuge speed (rpm) after calcination at 450°C and 550°C for vegetable and soil samples, respectively. The homogeneity of samples, linearity, detection and quantification limits were also determined. The quench curve was calculated to establish the parameters to program the LSC. Six 45Ca sample replicates were measured with a coefficient of variation (CV) of 1.74%, which indicates good sample homogeneity. The method is linearity over the range of activity studied for 0–30,000 disintegrations per minute (dpm). Our results suggest that the optimum homogenized sample preparation for calcination purposes was lyophilization. Techniques using 45Ca applied to soil and plant tissues are promising tracers of Ca in plants, which can be very useful for the study of Ca kinetics in plants and can serve to guide efficient fertilization programs.  相似文献   
17.
The biotic diversity of Strombus gigas has not been thoroughly studied despite the status of the queen conch as an important ecological resource. The bacteria associated with the conch influence their host in several ways, including through the metabolism of nutrients, protection against invasive bacteria and the regulation of the physical conditions. In this study, conventional microbiological methods and molecular tools such as denaturing gradient gel electrophoresis (DGGE) were used to assess the composition of the bacterial communities associated with the queen conch (S. gigas) in wild and captive habitats in Colombia. A genetic analysis of the bacterial communities revealed a high level of diversity based on the large number of bands detected using DGGE. In addition, differences in bacterial community structure were found between the conchs in captivity and the wild populations. The dominant phylogenetic affiliations of the bacteria, as determined using 16S rRNA gene sequencing, were grouped into four classes, namely, Betaproteobacteria (16%), Gammaproteobacteria (70%), Firmicutes (7%) and Actinobacteria (2%). These groups are related to host defence processes and the decomposition of organic matter. The 16S rDNA sequence analysis of the cultured bacteria and the resulting DGGE profiles are useful tools for characterizing the diversity of the bacteria associated with the analyzed conchs.  相似文献   
18.
We report the equine (Equs equs) and elk (Cervus elaphus) pituitary pre-prolactin (PRL) cDNA cloning, and their nucleotide and deduced amino acid sequences. Pre-PRL cDNA was obtained by RNA ligation mediated-rapid amplification of cDNA ends (RLM-RACE) and polymerase chain reaction (PCR). The elk pre-PRL cDNA exhibits two polymorphisms at positions 96 and 672, which are silent since they encode for the same amino acids, proline and isoleucine, respectively. We found no polymorphisms in the equine pre-PRL cDNA. The deduced amino acid sequence of the equine pre-PRL is 99% identical to the previously reported protein sequence. Pre-PRL mRNA is <1 kb in length and is highly expressed in the anterior pituitary gland, as demonstrated by Northern hybridization analysis. In summary, we cloned and sequenced the equine and elk pre-PRL cDNAs. The deduced amino acid sequence of elk and equine pre-PRL appears to be moderately conserved among other mammalian species. The polymorphic sites found in the elk cDNA could potentially be used in parentage testing and gene mapping.  相似文献   
19.
New Forests - Eriobotrya japonica is a non-native tree expanding in secondary forests and threatening the tropical montane cloud forest of central Veracruz, Mexico. Our objective was to investigate...  相似文献   
20.
A current view is that cytotoxic stress, such as DNA damage, induces apoptosis by regulating the permeability of mitochondria. Mitochondria sequester several proteins that, if released, kill by activating caspases, the proteases that disassemble the cell. Cytokines activate caspases in a different way, by assembling receptor complexes that activate caspases directly; in this case, the subsequent mitochondrial permeabilization accelerates cell disassembly by amplifying caspase activity. We found that cytotoxic stress causes activation of caspase-2, and that this caspase is required for the permeabilization of mitochondria. Therefore, we argue that cytokine-induced and stress-induced apoptosis act through conceptually similar pathways in which mitochondria are amplifiers of caspase activity rather than initiators of caspase activation.  相似文献   
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